Precision Alumina Ceramic Ring for Sealing, Insulation & Fixturing
St.Cera’s ceramic ring is precision machined from 99.8% high-purity alumina (Al₂O₃) for applications requiring high wear resistance, electrical insulation, and thermal stability up to 1600°C. Our manufacturing capabilities support outer diameters up to 600mm, thickness up to 100mm, and inner diameters as small as 0.2mm, with flatness of 0.003mm, parallelism of 0.002mm, and concentricity of 0.01mm. Available as seal rings, spacer rings, retaining rings, or custom profiles. The material’s zero porosity and chemical inertness make it suitable for aggressive chemical and plasma environments.
Specifications (based on 99.8% Al₂O₃ & St.Cera manufacturing capabilities):
| Property | Value |
| Material | 99.8% Alumina (Ivory) |
| Density | 3.93 g/cm³ |
| Flexural Strength | 361 MPa |
| Vickers Hardness | 16 GPa |
| Dielectric Strength | 15×10⁶ V/m |
| Max Outer Diameter | 600mm |
| Min Inner Diameter | 0.2mm |
| Max Thickness | 100mm |
| Flatness | 0.003mm |
| Parallelism | 0.002mm |
| Concentricity | 0.01mm |
| Surface Finish | Ra0.1 (lapped) |
| Max Operating Temp | 1600°C |
Applications:
- · Mechanical seal rings in pumps and mixers
- · Spacer and retaining rings in semiconductor fixtures
- · Electrical insulation rings in high-voltage equipment
- · Vacuum chamber sealing rings (with appropriate gasket)
Manufacturing Precision:
Straightness: 0.005mm, perpendicularity: 0.005mm, roundness: 0.002mm, verified by CMM.
Advantages:
- · Non-magnetic, non-conductive, corrosion-resistant
- · No particle generation – ideal for cleanroom use
- · Maintains dimensional stability under thermal cycling
Customization:
Custom cross-sections (rectangular, square, stepped), mounting holes, and locating notches available.
